It was impossible for a soldier like Trajan to endure the conditions accepted by Domitian; but the conquest of Dacia had become one of the most formidable tasks that had ever confronted the empire.
He drove them out of Moesia across the Danube, where he left them in possession of Dacia, which he did not think himself able to retain; the name was transf erred to Moesia, which was then called Dacia Aureliani.
One horde settled under Roman protection in Little Scythia (the Dobrudzha), others in Dacia Ripensis (on the confines of Servia and Bulgaria) or on the southern borders of Pannonia.
Cogalniceanu published various reviews, some of a political, others of a more literary character, such as the Dacia literar y (1840) and Archiva romdneasca (1845-46); he has also the great merit of having published for the first time a collection of the Moldavian chronicles.
He defeated the Chatti, annexed the district of the Taunus, and established the Limes as a line of defence; but he suffered defeats at the hands of the Quadi, Sarmatae and ' Marcomanni; in Dacia he received a severe check, and was obliged to purchase peace (90) from Decebalus by the payment of a large sum of money and by guaranteeing a yearly tribute - the first instance in Roman history.
From Antioch Hadrian set out for Dacia to punish the Roxolani, who, incensed by a reduction of the tribute hitherto paid them, had invaded the Danubian provinces.
An arrangement was patched up, and while Hadrian was still in Dacia he received news of a conspiracy against his life.